Wireless communication networks, such as wireless wide-area network or wireless local-area networks (WLAN) such as IEEE 802.11 wireless communication networks are able to provide communications for their users utilizing wireless access support through local access points. The access points serve to transfer communication traffic between a communication device in a local wireless domain to a backhaul connection, such as the internet for example. In particular, an Access Point (AP) and a switch of the network takes communications with the communication device and from there the communications can be routed to a wired, or another wireless, domain.
As in any communication network, there is always a need to support older, legacy devices that are operable using older technologies, while introducing newly evolving technologies. For example, IEEE 802.11 based systems originated with IEEE 802.11b CCK (Complementary Code Keying) based systems which then evolved to IEEE 802.11g/a OFDM (Orthogonal Frequency Division Multiplexing) based systems. There was tremendous effort in the IEEE 802.11g/a implementation to provide backward compatibility to IEEE 802.11b systems. Now the even newer IEEE 802.11n specification must also deal with the legacy IEEE 802.11a/b/g systems. Therefore, the access points of a WLAN network need to support many devices operable on different system.
Considering a practical scenario, IEEE 802.11g access points need to support IEEE 802.11b mode devices and now IEEE 802.11n access points need to support both IEEE 802.11b and IEEE 802.11g/a mode devices. The need to provide all of this “mixed-mode” support, and all the necessary communication overhead, tends to lower overall network throughput. This problem will continue to exist in the future when there is new protocol like IEEE 802.11n++ (Gigabit Wi-Fi Alliance) that would need to support three previous legacy systems.
One solution to the problem has been to simply limit legacy client support on access points by static configuration. However, this is very inefficient and difficult to implement, one access point at a time. In addition, there is chance of a legacy mobile device being unable to obtain service due to the absence of a nearest access point providing the necessary legacy service. Another solution is to implement load balancing across frequency bands of a dual-band access point. However, this solution does not address mixed-mode system operation within multiple access points.
Accordingly, there is a need for new techniques to alleviate mixed-mode operations in a wireless communication network.
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